The National Telecommunications Information Administration (NTIA) is the executive branch's advisory agency on telecommunications issues. In the early 1980s, this agency proposed a plan to raise awareness of a single emergency telephone number to the general public. From that program, the National Emergency Number Association (NENA), a non-profit organization, was created. NENA has since become a leading organization to improving technology and developing guidelines for 9-1-1 (“911”) telephone calls (i.e., emergency telephone calls) to improve response by emergency rescue teams.
Telecommunications have been changing rapidly over the past several years primarily since the development and growth of the mobile telephone industry and the Internet. New forms of telecommunications have been developing as well. Traditional telecommunications were performed over the public switch telephone network (PSTN). A system to maintain location of subscribers of telecommunications companies operating on the PSTN was developed. Determining the location of subscribers of the telecommunications companies was relatively easy as the locations of telephones were known by the telecommunications companies or carriers due to installing the telephones, establishing billing, or otherwise. However, with the new forms of telecommunications, subscribers are able to use wireless devices that may access different wireless access points to communicate over a communications network, such as the Internet. One common interface for wireless access to a communications network includes the IEEE 802.11 communications protocol, which is commonly known by the brand name Wireless Fidelity or WiFi. Wireless devices are being configured to have WiFi communications protocols to enable a subscriber to access WiFi enabled access points. Many WiFi enabled wireless devices have global positioning system (GPS) capabilities that are able to communicate GPS location information (i.e., latitude and longitude geographical coordinates) of the WiFi enabled device. While GPS location information may be helpful to track or locate a person at a precise geographical location, such information is not extremely useful in an emergency situation where emergency rescue personnel, such as firemen and police, better understand physical address location information (e.g., street address) for performing an emergency rescue in an emergency situation.
A public safety answering position (PSAP) is used by emergency services to answer calls from the public to notify emergency personnel to respond to an emergency situation. Traditionally, a caller would contact a PSAP and provide location information during the telephone call. When caller identification (i.e., caller ID) was introduced, PSAPs were installed with telephone systems compatible with caller ID to identify names and phone numbers of individuals placing emergency 911 calls. This first version of caller ID is known as type I caller ID. Type I caller ID operates in a single data message format (SDMF) or multiple data message format (MDMF) that provide a caller's telephone number, date, and time of the call during the ringing interval.
A second type of caller ID or type II caller ID was later developed to communicate name and telephone number information of a calling party to a called party when a call between a called party and a first calling party is in progress. Type II caller ID uses a multiple data message format (MDMF) that communicates a caller's name, telephone number, date, and time. Enhanced 911 is a North American Telephone Network (NATN) feature of the 911-emergency-calling system that uses a reverse telephone directory provided by cellular telephone companies to determine location information of a caller.
There are two types of E911 systems that operate within the United States, Phase I and Phase II. E911 Phase I systems are required to provide an operator with the telephone number, originator, and location of the cell site or base station receiving a 911 call. E911 Phase II systems are required to provide an operator with the telephone number, originator, GPS coordinates, location of the caller with a higher degree of accuracy than E911 Phase I, and use automatic location identification (ALI) database at the PSAP that is used to provide physical address location information to a PSAP operator. However, only 18% of all PSAPs are configured with E911 Phase II systems. The remaining 82% of PSAPs are configured with E911 Phase I systems, which are incapable of handling GPS coordinates, and, therefore, subscribers who have wireless telephones that use GPS coordinates for 911 emergency calls cannot be properly serviced by these PSAPs. If a caller is using a non-cellular wireless device, such as a WiFi enabled wireless device (e.g., softphone), or if a caller is using any other Voice-Over-Internet Protocol (VoIP) based phone, an operator at a PSAP with E911 Phase I capabilities is unable to determine address location based on GPS coordinates that are received from the caller. As softphones are often used in laptop computers that are moved from one network access point, such as a WiFi access point to another, emergency 911 calls may be placed from locations other than a user's home. Many newer laptop computers are installed with GPS capabilities to be used for certain applications, such as emergency 911 calls. Softphones and other wireless devices with GPS capabilities suffer from the limitations described above. Currently, there is no way to ensure that the PSAP will receive a current physical address location of a caller in the event the wireless devices are physically moved.